Don't know what your points limit is but this seems really light on stuff. I can't reconcile this list with the magic sauce of the chaos codex (limited though it may be) such as stratagems with bringing back full strength cultists etc.

As you aren't seeming to go down the CP/stratagem route, perhaps you should change formation to a battalion (9 CP is a brigade) so you can chop some of the stuff which seems to be space fillers. The differing speeds of the brutes and bikes means they won't hit at the same time and I'd be worried you'd hit piecemeal. The plasma only really gets good in 12" so you lose the Alpha advantage.

I would personally be trying to go for cheaper elites and less bikes if I was going to keep a brigade - but actually don't really rate hellbrutes and think you would be better off with bigger troops units, less HQ and getting a sorceror in.